Not waterfalls exactly but a fascinating and little-known consequence of frozen waterfalls: https://www.youtube.com/watch?v=9V9p4mFEYXc

(All those Yosemite Nature Notes videos are worth watching, if you need something to watch while you munch your sandwich.)

that vid of kayakers on cauldron snout is rubbish…nowt but a trickle.
catch it in winter and it is a terrifying raging monster.

This is a better kayaking video of the Snout

https://vimeo.com/31443429

https://en.wikipedia.org/wiki/Crackpot,_North_Yorkshire

certainly ‘refreshing’ if you stand under them

Park at Low Force (near Middleton in Teesdale), walk up to High force and then Cauldron Snout, then walk back and swim at Low Force – got great childhood memories of that, and warm sunny days on the riverbanks by Low Force.
Or bike up to Tarf Falls up Glen Tilt and have a swim in them as part of the classic loop from Blair Atholl.

Gaping Gill?

[url=https://flic.kr/p/6Unnd2]Gaping Gill 2[/url] by Ben Cooper, on Flickr

Oh go on then I’ll do it,

I like the one in my garden.

For novelty, there’s always Kinder Upfall when the wind blows the right way